The present invention relates in general to coupling means for connecting conduits in a subsea well installation, and particularly to a coupling suitable for connecting large diameter well conduits such as a marine riser or conductor to a blowout preventer stack, or a blowout preventer stack or christmas tree to the well head.
Drilling operations in subsea well installations are normally conducted through a marine conductor or riser which extends from an overhead platform or floating vessel with the riser or conductor running down through the sea to the well head positioned at the ocean bottom. By virtue of movement of the vessel, or bending movement of the marine riser or conductor, due to ocean currents, there is frequently a very high separation loading placed on the connectors between the marine riser and the well head apparatus. It is therefore a primary object of the present invention to disclose and provide an improved marine conductor coupling suitable for connecting a marine conductor or riser run from a floating vessel or overhead platform to the well head apparatus with the coupling being interposed between the riser and well head associated blowout preventer apparatus, between the blowout preventer apparatus and the well head in drilling operations, between the christmas tree and well head in production operations or between any other subsea conduits where a high loading separation force is anticipated and it is necessary to have a repeated connection and disconnection of the coupling members.
It is a further object of the present invention to provide a marine conductor coupling as in the foregoing object wherein the coupling has a low-profile, is a high-pressure connector faciliating inclusion of a metal-to-metal seal between connected conduits and is able to withstand high separation loading applied to the coupling due to forces tending to pull the connector away from the well head conduit to which it is connected.